1. Field of the Invention
The field of the invention is data processing, or, more specifically, methods, apparatus, and products for remotely booting computing nodes in a switching domain.
2. Description of Related Art
The development of the EDVAC computer system of 1948 is often cited as the beginning of the computer era. Since that time, computer systems have evolved into extremely complicated devices. Today's computers are much more sophisticated than early systems such as the EDVAC. Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, and so on. As advances in semiconductor processing and computer architecture push the performance of the computer higher and higher, more sophisticated computer software has evolved to take advantage of the higher performance of the hardware, resulting in computer systems and networks today that are much more ubiquitous and powerful than just a few years ago.
As these computer systems and networks have advanced, system administrators have developed tools to better manage these computer systems. One such tool is the Wake-On-LAN mechanism that provides a system administrator with the ability to remotely activate a computer system that has been shut down. Due to security, power conservation, or other concerns, users often turn off their computers when anticipating a long period of non-use. Using the Wake-On-LAN mechanism provides system administrators with the flexibility to allow users to turn off their computers but retain the system administrator's ability to backup or upgrade the computer system remotely during those periods of non-use when the computer is often shut down.
The Wake-On-LAN mechanism operates by reserving a relatively small amount of power for a computer's network adapter while the computer is shut down. The network adapter listens for a specific wakeup packet, often referred to as the ‘magic packet,’ that is transmitted from some other administrative computer on the network. The wakeup packet is typically implemented as a User Datagram Protocol (‘UDP’) packet that is broadcast on the network subnet's broadcast address. The data that is contained in a wakeup packet is a defined constant as represented in hexadecimal as ‘FF FF FF FF FF FF’ followed by sixteen repetitions of a Media Access Control (‘MAC’) address for the computer system to be activated, which may be further followed by a four or six byte password. Upon receiving the wakeup packet, the network adapter validates the wakeup packet. If the wakeup packet is valid, the network adapter may signal the computer system's Basic Input/Output System (‘BIOS’) to turn on power to the other components of the computer and initiate the boot sequence. Readers will note that although the acronym ‘LAN’ in ‘Wake-On-LAN’ refers to a ‘Local Area Network,’ the Wake-On-LAN mechanism is not restricted for use only within a LAN. Rather, a system administrator may utilize the Wake-On-LAN mechanism across different types of networks including Wide Area Networks (‘WAN’) or the Internet.
The drawback to the current Wake-On-LAN mechanism, however, is that the computer to be activated is often installed behind a firewall that does not permit broadcast network traffic to pass through to the computers behind the firewall. As such, the wakeup packet never reaches the computer to be activated. Another drawback to the current Wake-On-LAN mechanism is that the system administrator often does not know the MAC address for the computer to be activated. Without such knowledge of the computer's MAC address, a wakeup packet cannot be generated.